September Weather in Stellenbosch, South Africa

Last updated: August 31, 2025

In September, Stellenbosch, South Africa, experiences a pleasant transition into spring, with daytime temperatures peaking at a maximum of 29°C (85°F). The average temperature hovers around a mild 14°C (57°F), providing a comfortable climate for outdoor activities. Nighttime brings cooler air, with temperatures dipping to a minimum of 6°C (42°F). While this month sees 58 mm (2.3 in) of rainfall across approximately 9 days, the air retains a noteworthy humidity level of 76%, contributing to lush landscapes and vibrant flora. Overall, September offers a refreshing ambiance characterized by warm days and cool evenings, perfect for exploring the scenic beauty of Stellenbosch.

September Temperature in Stellenbosch

As September arrives in Stellenbosch, South Africa, the temperatures begin to reflect the transition from winter to spring. With minimums around 6°C (42°F) and a comfortable average of 14°C (57°F), the region experiences a gentle warming trend. The maximum temperatures can reach a pleasant 29°C (85°F), providing ample opportunity for outdoor exploration. This month stands out as a bridge between the cooler winter months, where temperatures linger around their lowest, and the warmer summer that follows. As the landscape blooms, September invites both locals and visitors to savor the invigorating air and vibrant scenery of this charming town.

September Weather in Stellenbosch: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Stellenbosch, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Stellenbosch, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec697067635956545457606366
Data source: Temperature data for Stellenbosch generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Stellenbosch

September in Stellenbosch marks a transition from the winter months, bringing 58 mm (2.3 in) of rain over approximately 9 days. This increase in precipitation, compared to the drier summer months of January and February, signals the arrival of spring, as the region begins to warm up. While not as wet as the mid-winter peaks seen in June and July, September's rainfall is crucial for agriculture, especially in vineyards preparing for the upcoming growing season. The gentle rains pave the way for vibrant blossoms and set the stage for what is expected to be a bountiful season ahead, reflecting a consistent pattern of moderate rainfall as the year progresses.

September Precipitation Trends in Stellenbosch

The chart displays monthly precipitation patterns in Stellenbosch, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Stellenbosch, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec20123037801321179158524631
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Stellenbosch

September in Stellenbosch, South Africa, welcomes a gentle decline in humidity, settling at 76%. This marks a slight decrease from the wetter months of late winter and early spring, which typically hover around the 77% to 81% range. As September transitions the region toward warmer days, the overall trend reflects a gradual shift towards lower humidity levels, a precursor to the more arid months ahead. This change often enhances the region's crisp, vibrant atmosphere, making it an ideal time for outdoor explorations and vineyard visits, while still holding onto a trace of the lingering humidity of winter.

September Average Humidity in Stellenbosch

This chart illustrates the average monthly humidity levels in Stellenbosch, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Stellenbosch is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec77%80%81%80%78%79%80%77%76%77%75%78%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Stellenbosch

As September rolls into Stellenbosch, South Africa, the UV Index reaches 9, categorizing it as very high, with a burn time of just 15 minutes. This reflects a notable uptick from the preceding months, aligning closely with the higher indices seen in early spring and summer. Following the moderate summer months of June and July, which featured UV values of 4, the gradual rise indicates a return to intense sunshine, urging residents and visitors alike to take caution against overexposure. With severe levels peaking again in October at 11, it's essential to stay protected during these vibrant early spring days. For more detailed insights on the UV Index throughout the year, visit Stellenbosch UV Index.

Maximum UV Index Levels in Stellenbosch for September

The chart shows the monthly maximum UV Index (UVI) for Stellenbosch in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Stellenbosch typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec141311854469111214
Data source: Stellenbosch September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Stellenbosch

As September graces Stellenbosch, the warmth of the transition towards summer is palpable, with 327 hours of sunshine illuminating the vineyards and mountains. This marks a slight dip from the bustling sunshine of the preceding months, yet it reflects the gentle shift into spring that enhances the region's vibrant scenery. Following the relatively cooler winter months, where sunshine hours dipped into the 260s, September’s light begins to rejuvenate the landscape, setting the stage for a spectacular October surge of 374 hours. This trend not only signals a natural increase in warmth but also invites visitors to experience the breathtaking beauty of Stellenbosch in a flourishing season. The gradual build-up to summer becomes apparent as Stellenbosch moves from the comfortable embrace of spring into the sun-kissed days of late year, making it a perfect time for exploration and enjoyment.

Monthly Sunshine Duration in Stellenbosch: September Highlighted

The September sunshine duration represents the total number of hours Stellenbosch experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec340h359h354h313h290h266h287h309h327h374h390h421h
Data source: Stellenbosch September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Stellenbosch During September

In Stellenbosch, South Africa, September typically ushers in moderate sunshine, with a 56% chance of sunny days. As summer’s warmth begins to linger, the likelihood of clear skies is noticeably lower than the sun-drenched summer months of January and February, both boasting an impressive 82% chance of sun. However, September marks a transitional period, with sunny weather becoming more stable than during the cooler months that precede it. While it isn’t the sunniest month, it provides a promising hint of the vibrant days ahead as day temperatures start to rise, bridging the gap towards the approaching spring.

Percentage of Sunny Days in September in Stellenbosch

The chart illustrates the percentage of sunny days in Stellenbosch throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Stellenbosch experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec82%83%55%58%52%56%59%56%56%53%53%58%
Data source: Stellenbosch September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Stellenbosch in September

In Stellenbosch, South Africa, the month of September brings a gentle transition as daylight hours increase to an average of 11 hours. This marks a notable shift from the colder, shorter days of winter months like June and July, which offer only 9 to 10 hours of light. As spring approaches, daylight begins to lengthen, signaling the end of winter’s grip and the awakening of nature. Following September, the days continue to grow longer, peaking in January with a generous 14 hours. This rhythmic ebb and flow of daylight not only highlights the changing seasons but also invites residents and visitors alike to embrace the outdoors as the days gradually grow warmer and more luminous.

Average Daylight Hours in Stellenbosch for September

The chart illustrates the variation in daylight duration in Stellenbosch throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec14h 6m13h 17m12h 14m11h 12m10h 20m9h 54m10h 8m10h 53m11h 53m12h 56m13h 52m14h 21m
Data source: Stellenbosch daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Stellenbosch

As September ushers in the change of seasons in Stellenbosch, South Africa, the average wind speed registers at a refreshing 4.4 m/s (10 mph), making it a delightful month for outdoor enthusiasts. Following a gradual decline from the summer months, September's winds pick up slightly compared to the previous months, hinting at the transitional shift towards spring. While the winds are milder than the summer peak, they offer a gentle breeze that complements the stunning landscapes and vibrant vineyards, painting a picturesque scene for visitors and locals alike. With wind speeds stabilizing in October and November at the same pace, September serves as a delightful reminder of nature's rhythm, where every gust carries the promise of rejuvenation.

Average September Wind Speed in Stellenbosch

The chart displays monthly wind speed patterns in Stellenbosch, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec4.94.84.13.83.13.73.83.54.4 m/s4.34.44.5
Data source: Stellenbosch September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Stellenbosch Compares to Other Months

Weather in Stellenbosch varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Stellenbosch, focusing on differences in temperature, rainfall, humidity, and UV levels.

September and January showcase distinct weather patterns. In September, temperatures range from a minimum of 6°C (42°F) to a maximum of 29°C (85°F), with an average temperature of 14°C (57°F). This month experiences more rainfall, totaling 58 mm (2.3 in) over 9 days, and humidity levels sit at 76%.

In contrast, January boasts warmer temperatures, with a minimum of 13°C (55°F) and a maximum of 32°C (90°F), averaging 21°C (70°F). It is also significantly drier, seeing only 20 mm (0.8 in) of precipitation over just 3 days, while humidity slightly increases to 77%. For a closer look at January's weather specifics, you can visit Stellenbosch weather in January.

September and February present notable differences in weather patterns. September often experiences cooler temperatures, ranging from a minimum of 6°C (42°F) to a maximum of 29°C (85°F), with an average of 14°C (57°F). Additionally, this month sees about 58 mm (2.3 in) of precipitation over approximately 9 days, resulting in a humidity level of 76%. In contrast, February is noticeably warmer, with temperatures ranging from a minimum of 13°C (56°F) to a maximum of 31°C (89°F) and an average of 21°C (70°F). Precipitation in February is significantly lower at 12 mm (0.5 in), occurring over just 3 days, while humidity rises slightly to 80%. For more detailed information, check out Stellenbosch weather in February.

When comparing the weather in September and March, we see distinct differences in temperature and precipitation. September exhibits a wider temperature range, with a minimum of 6°C (42°F) and a maximum of 29°C (85°F), while March starts warmer, with temperatures ranging from 12°C (54°F) to 32°C (90°F). In terms of rainfall, September receives more precipitation at 58 mm (2.3 in) over 9 days, compared to March, which sees only 30 mm (1.2 in) over 4 days. Humidity levels are slightly higher in March at 81%, compared to 76% in September. For a more detailed look at the climate specifics in March, you can visit Stellenbosch weather in March.

When comparing the weather in September and April, notable differences emerge. September experiences a wider temperature range, with minimums reaching 6°C (42°F) and maximums peaking at 29°C (85°F), resulting in an average of 14°C (57°F). In contrast, April generally presents milder conditions, with minimum temperatures at 10°C (50°F) and maximums hitting 32°C (91°F), averaging 17°C (63°F). Precipitation is also less frequent in April, with only 37 mm (1.5 in) falling over approximately 5 days, compared to September’s 58 mm (2.3 in) over 9 days. Both months showcase high humidity levels, with April at 80% and September at 76%. For a detailed look at April's conditions, visit Stellenbosch weather in April.

In comparing the weather between September and May, both months show a mild temperature range, with September featuring a minimum of 6°C (42°F) and a maximum of 29°C (85°F), while May has slightly warmer temperatures, with a minimum of 7°C (45°F) and a maximum of 27°C (81°F). The average temperatures are also comparable, with only a small difference of 1°C (2°F) favoring May. However, September tends to be drier, with 58 mm (2.3 in) of precipitation over 9 days, compared to May's 80 mm (3.2 in) over just 8 days. Humidity levels are relatively high in both months, at 76% in September and 78% in May. For more specific details on the weather in May, you can visit Stellenbosch weather in May.

When comparing the weather in September and June, we see some notable differences. September typically features a broader temperature range, with morning lows around 6°C (42°F), average temperatures hitting 14°C (57°F), and warm afternoons reaching up to 29°C (85°F). In contrast, June's temperatures are slightly cooler, with a minimum of 6°C (43°F), an average of 13°C (56°F), and a maximum of 25°C (77°F).

Precipitation levels also vary between the two months; September sees about 58 mm (2.3 in) of rainfall over 9 days, while June experiences a much wetter climate with 132 mm (5.2 in) spread over 11 rainy days. Humidity in both months is relatively similar, hovering around 76% in September and 79% in June. For a more detailed look at June's weather, consider checking Stellenbosch weather in June.

When comparing the weather in September to July, September tends to be slightly warmer with average temperatures ranging from a minimum of 6°C (42°F) to a maximum of 29°C (85°F), while July has a narrower range with minimums of 5°C (41°F) and maximums of 25°C (77°F). Additionally, September experiences less precipitation, with 58 mm (2.3 in) over 9 days compared to July's 117 mm (4.6 in) over 10 days. Humidity levels are also quite similar, with September at 76% and July at 80%. For those interested in the specifics of July's climate, detailed information can be found at Stellenbosch weather in July.

Comparing the weather in September and August reveals some notable differences. September experiences slightly warmer temperatures, with a minimum of 6°C (42°F) and a maximum of 29°C (85°F), compared to August’s range of 5°C (41°F) to 26°C (78°F). The average temperature in September is also higher at 14°C (57°F), compared to August's average of 12°C (54°F). In terms of precipitation, September has 58 mm (2.3 in) over 9 days, which is less than August's 91 mm (3.6 in) over 13 days, indicating that September tends to be somewhat drier. Humidity levels are similar, with September at 76% and August at 77%. For more detailed insights, you can check Stellenbosch weather in August.

In September, the weather starts to transition with temperatures ranging from a minimum of 6°C (42°F) to a maximum of 29°C (85°F), averaging around 14°C (57°F). The month experiences 58 mm (2.3 in) of precipitation over 9 days, along with a humidity level of 76%. In comparison, October shows a slight increase in the average temperature to 16°C (61°F), while the maximum reaches 30°C (86°F). Precipitation decreases slightly to 52 mm (2.1 in) over just 7 days, and humidity remains comparable at 77%. For more detailed weather information, you can check Stellenbosch weather in October.

In comparing the weather of September and November, September showcases a wider temperature range with a minimum of 6°C (42°F) and a maximum of 29°C (85°F), while November features slightly higher minimum and average temperatures, with a low of 9°C (48°F) and an average of 17°C (63°F). Precipitation is more frequent in September, with 58 mm (2.3 in) over 9 days, compared to November's 46 mm (1.8 in) spread over just 5 days. Both months have similar humidity levels, hovering around 75-76%. For more detailed information, you can check Stellenbosch weather in November.

When comparing the weather in September to that in December, notable differences emerge. September typically enjoys a milder temperature range, with minimums around 6°C (42°F) and maximums reaching up to 29°C (85°F), while December sees a warmer setting with minimum temperatures around 12°C (54°F) and maximums peaking at 31°C (89°F). Precipitation is more frequent in September, averaging 58 mm (2.3 in) over 9 days, compared to December's lighter 31 mm (1.2 in) over just 6 days. Humidity levels remain similar, with September at 76% and December slightly higher at 77%. For more detailed insights on December weather, check out Stellenbosch weather in December.

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Conclusion: What to Expect From September Weather in Stellenbosch

As September rolls in, Stellenbosch experiences a delightful transition into spring, marked by notable shifts in weather patterns compared to the cooler winter months. The average temperatures start to rise, providing a pleasant warmth during the day, while still allowing for cooler evenings. With a moderate amount of rainfall spread over several days, the scenery becomes lush and vibrant, setting the stage for a beautiful blooming landscape. This month also sees a noticeable increase in humidity, creating a unique atmosphere that enhances the charm of the region. For a deeper insight into how this seasonal change impacts the area's climate, visit Stellenbosch Climate.